*{
    padding: 0;
    margin: 0;
}
.nav-bar{
    height: 50px;
    color: #fff;
    display: flex;
    align-items: center;
}
.left{
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: blue;
}
.center{
    flex: 1;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: red;
}
.right{
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: skyblue;
}